How to stop thinking about her?

The last few days my mom has been on my mind.. she passed away about 3?5 years ago. I don't know why but she keep coming to me. I have cried myself to sleep the past three nights in a row. Today at work a customer came in to by booze with the birthday of 01/21/73. Which is my mom's birthday. And I broke down crying while on the clock. I'm scared to go to sleep tonight because I'm afraid I'm gonna think about her. How can I stop myself from thinking about how much I miss my mom
How to stop thinking about her?
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